gistfile1.js

int sig = 0;
int spd=255; //1~255の値にする

void setup(){
  Serial.begin(9600);
  pinMode(2,OUTPUT);//左モーター用ドライバピン
  pinMode(4,OUTPUT);//左モーター用ドライバピン
  pinMode(7,OUTPUT); //右モーター用ドライバピン
  pinMode(8,OUTPUT); //右モーター用ドライバピン
  motor_stop();
}

void motor_stop(){
  digitalWrite(2,LOW);
  digitalWrite(4,LOW);
  analogWrite(5,1);
  digitalWrite(7,LOW);
  digitalWrite(8,LOW);
  analogWrite(9,1);
  Serial.println("motor_stop");
}

void motor_go(){
  digitalWrite(2,HIGH);
  digitalWrite(4,LOW);
  analogWrite(5,spd);
  digitalWrite(7,HIGH);
  digitalWrite(8,LOW);
  analogWrite(9,spd);
  Serial.println("motor_go");
}

void motor_back(){
  digitalWrite(2,LOW);
  digitalWrite(4,HIGH);
  analogWrite(5,spd);
  digitalWrite(7,LOW);
  digitalWrite(8,HIGH);
  analogWrite(9,spd);
  Serial.println("motor_back");
}

void motor_left(){
  digitalWrite(2,HIGH);
  digitalWrite(4,LOW);
  analogWrite(5,spd);
  digitalWrite(7,LOW);
  digitalWrite(8,HIGH);
  analogWrite(9,spd);
  Serial.println("motor_right");
}

void motor_right(){
  digitalWrite(2,LOW);
  digitalWrite(4,HIGH);
  analogWrite(5,spd);
  digitalWrite(7,HIGH);
  digitalWrite(8,LOW);
  analogWrite(9,spd);
  Serial.println("motor_left");
}

void loop(){
  if(Serial.available()>0){//データの読み込み
    sig=Serial.read();
    switch(sig){
      case 'a':
        motor_go();
        delay(5000);
        break;
        
      case 'b':
        motor_back();
        delay(5000);
        break;
        
      case 'c':
        motor_left();
        delay(5000);
        break;
      
      case 'd':
        motor_right();
        delay(5000);
        break;
    }
  }
  motor_stop();
}